is anyone doing encrypted backups of folders or files, and splitting the backup into volumes?

Tar (or the file system?) seems to have a limit at 8GB (too big to be practical anyway, I prefer chunks of 700MB or 2048MB), and using it with encryption I haven't tried to figure out yet

p7zip does not store Unix file access rights by itself, so it needs piping from tar, but then you run into a limit on the path name of 256 characters (try saving a webpage): "tar: File name too long for ustar "

I'm trying all this on a box with OpenBSD 4.5 i386, but I've got 2 boxes with 4.6 to play with too.

I use the RAR package on my old OpenBSD 3.9 fileservers, but i's time to install 4.6 on them, me thinks

The pax tool can use cpio or tar formats and can manage multiple volumes, but it has the limitations of the underlying format. On the other hand, dump/restore has none of the other formats' restrictions, but it cannot handle multiple volumeswith media that does not have end-of-volume marks, so it is limited to tape drives. For the same reason, it cannot manage multivolume via named pipes.

I use dump and restore to avoid the limitations of tar, gtar, cpio, or pax. The output is piped through gzip and piped to a storage server via ssh. On the storage server, offsite backup is done to DVD+RW, with dump again, and the multivolume is managed through through two tools: flyisofs and shunt, from sysutils/shunt. This breaks the streams into 4.3GB chunks piped into growisofs, from sysutils/dvd+rw-tools.

Here's an example of using shunt and flyisofs for backup, then shunt for restore. The files to be backed up are already gzipped dump files, but you could add piping to openssl enc, gzip, what ever you want. .

The restore example concatenates files from multiple mount sequences of DVDs, and concatenates them into a single pipe into restore(1). To restore individual files, use restore(1) in interactive mode. Change the restore operands from "-rf -" to "-if -" to interactively restore from standard input. To add decryption or decryption, pipe the stream through openssl(1) with the enc operand.

The restore example concatenates files from multiple mount sequences of DVDs, and concatenates them into a single pipe into restore(1). To restore individual files, use restore(1) in interactive mode. Change the restore operands from "-rf -" to "-if -" to interactively restore from standard input. To add decryption or decryption, pipe the stream through openssl(1) with the enc operand.

The restore(1) man page and the openssl(1) man page may be helpful.

Excellent, thanks for persevering, jggimi, I had no idea that restore could be interactive and pick out files or folders, for some reason I had it in my mind that it was all or nothing. I will study the man page.

Thanks for the info, that's an exciting piece of software, and I will be playing with it. I have many endusers who need this type of thing

However, I like to keep my server setups as simple/vanilla/minimalistic/KISS as possible, especially since my clients (small businesses) can not afford to run much of a serverfarm. By keeping the installs minimalistic, I speed up bare metal installs/repairs.

And having a command line way of restoring files, or whole backups, on a fresh install with the same tool as on a full install, is ace